Lesson 6: App navigation | Android Developers

Which of the following statements about fragments are true? Select all that apply.

Choose as many answers as you see fit.

You can use a Fragment in more than one Activity.

One Activity can have multiple fragments.

After you define a Fragment in a Kotlin class, the fragment is automatically added to the activity_main.xml layout file.

Use the <fragment> tag to define the place in a layout file where a Fragment is to be inserted.

How do you enable your project to use navigation components?

Make sure every Activity class extends the class NavigationActivity.

Use the NavigationController class as the launch activity.

Add uses-navigation to the AndroidManifest.xml file.

Add dependencies for navigation-fragment-ktx and navigation-ui-ktx in the build.gradle (module) file.

Where are the possible navigation routes through your app defined?

In a file (often called navigation.xml) in the res > layout folder.

In a file (often called navigation.xml) in the app > navigation folder.

In a file (often called navigation.xml) in the res > navigation folder.

In the AndroidManifest.xml file, under the element.

Which of the following statements about the NavHostFragment are true?

Choose as many answers as you see fit.

As the user moves between destinations defined in the navigation graph, the NavHostFragment swaps the fragments in and out as necessary.

You can click the NavHostFragment in the project view to open the navigation graph.

You add the NavHostFragment to the main layout by adding a fragment whose name is androidx.navigation.fragment.NavHostFragment.

You must create a single NavHostFragment subclass and implement the onNavigate() method to handle different kinds of navigation (such as button clicks)

Where do you set the ID of a fragment to be used in navigation?

In the fragment layout file, either by setting the ID attribute in the design editor or in the layout XML file in the res > layout folder.

In the project navigation file, either by setting the ID attribute in the navigation graph or in the navigation.xml file in the res > navigation folder.

You need to set the ID in both the navigation file for the app and the layout file for the fragment.

Set the ID variable in the relevant Fragment class.

Where do you define the items for a menu?

It depends on where the menu will be shown. For a navigation drawer menu, add an <item> tag for each menu item in the menu.xml file in the res > drawer folder. For the options menu, add an <item> tag for each menu item in the menu.xml file in the res > options folder.

In the layout file for the fragment or activity that displays the menu, add a <menu> tag that contains <item> tags for each item.

In a menu_name.xml file in the res > menu folder, add an <item> tag for each menu item. Create separate XML files for each separate menu.

In the AndroidManifest.xml file, add a <menus> tag that contains a <menu> tag for each menu, that in turn contains an <item> tag for each menu item.

What do you need to do to enable the overflow menu (also known as the options menu)? You can assume you have already defined the menu items.

Choose as many answers as you see fit.

Call setHasOptionsMenu(true) in onCreate() for an Activity or onCreateView() for a Fragment.

Implement onCreateOptionsMenu() in the Activity or Fragment to create the menu.

Set the onClick attribute in the menu.xml file to onShowOptionsMenu, unless you are implementing a custom onClick listener for the options menu, in which case specify the name of that custom listener instead.

Implement onOptionsItemSelected() in the Activity or Fragment to determine what happens when a user selects a menu item in the options menu.

What does the Safe Args Gradle plugin do? Select all that apply.

Choose as many answers as you see fit.

Generates simple object and builder classes for type-safe access to arguments specified for destinations and actions.

Creates Navigation classes that you can edit to simplify the passing of parameters between fragments.

Generates a method for each action that you have defined in the navigation graph.

Prevents your code from using the wrong key when extracting data from a bundle.